This invention relates to a redox-induced cationically polymerizable composition that exhibits reduced cure temperature and to a method for reducing the cure temperature of a cationically polymerizable composition.
In many manufacturing processes, processing speed leads to higher throughput and lower assembly costs. When the use of an adhesive, coating, or encapsulant is part of the manufacturing process, processing speed can be increased if the adhesive, coating, or encapsulant can be cured quickly at a relatively low curing temperature.
In the electronics packaging industry, for example, low temperature, fast (snap) cure adhesives and encapsulants are desired for various applications. A common mode of electronic packaging involves affixing semiconductor devices onto substrates by means of an adhesive or encapsulant. The more prominent uses are the bonding of integrated circuit chips to metal lead frames or organic substrates, and the bonding of circuit packages or assemblies to printed wire boards, including, for example, die attach for array package, die attach for RFID package, and component attach for ink jet cartridge assembly. For ink jet cartridge, low temperature cure assembly can minimize jetting trajectory distortion and improve printing quality. For temperature-sensitive components or substrates, such as, the paper-based antenna in RFID application and camera sensor in organic substrates, low temperature interconnect is very desirable. Thus, there is a need for polymerizable compositions that cure at low temperatures, preferably less than 100° C.